Dolby Vision for Minix U22X-J (Max) and Ugoos AM6+

as of the Jul18 nightly, CE does not support any sort of meaningful conversion of HDR to SDR, even if you enable SDR conversion in the CE settings and reboot. I posted about that here: Ugoos AM6B+ no HDR to SDR conversion

The subsequent posts in that thread link to the custom VS10 build of CE, which has excellent SDR conversion.